By exploiting the capabilities of steady-state electrochemical measurements, we have measured the inner diameter of a lipid nanotube using Fick’s first law of diffusion in conjunction with an imposed linear concentration gradient of electroactive molecules over the length of the nanotube. Fick’s law has been used in this way to provide a direct relationship between the nanotube diameter and the measurable experimental parameters Δi (change in current) and nanotube length. Catechol was used to determine the Δi attributed to its flux out of the nanotube. Comparing the nanotube diameter as a function of nanotube length revealed that membrane elastic energy was playing an important role in determining the size of the nanotube and was different when the tube was connected to either end of two vesicles or to a vesicle on one end and a pipet tip on the other. We assume that repulsive interaction between neck regions can be used to explain the trends observed. This theoretical approach based on elastic energy considerations provides a qualitative description consistent with experimental data.

BibTeX @article{Adams2010,author={Adams, Kelly L. and Engelbrektsson, Johan and Voinova, Marina V. and Zhang, Bo and Eves, Daniel J. and Karlsson, Roger and Heien, Michael L. and Cans, Ann-Sofie and Ewing, Andrew G},title={Steady-State Electrochemical Determination of Lipidic Nanotube Diameter Utilizing an Artificial Cell Model},journal={Analytical Chemistry},issn={1520-6882},volume={82},issue={3},pages={1020-1026},abstract={By exploiting the capabilities of steady-state electrochemical measurements, we have measured the inner diameter of a lipid nanotube using Fick’s first law of diffusion in conjunction with an imposed linear concentration gradient of electroactive molecules over the length of the nanotube. Fick’s law has been used in this way to provide a direct relationship between the nanotube diameter and the measurable experimental parameters Δi (change in current) and nanotube length. Catechol was used to determine the Δi attributed to its flux out of the nanotube. Comparing the nanotube diameter as a function of nanotube length revealed that membrane elastic energy was playing an important role in determining the size of the nanotube and was different when the tube was connected to either end of two vesicles or to a vesicle on one end and a pipet tip on the other. We assume that repulsive interaction between neck regions can be used to explain the trends observed. This theoretical approach based on elastic energy considerations provides a qualitative description consistent with experimental data.},year={2010},}

RefWorks RT Journal ArticleSR ElectronicID 111200A1 Adams, Kelly L.A1 Engelbrektsson, JohanA1 Voinova, Marina V.A1 Zhang, BoA1 Eves, Daniel J.A1 Karlsson, RogerA1 Heien, Michael L.A1 Cans, Ann-SofieA1 Ewing, Andrew GT1 Steady-State Electrochemical Determination of Lipidic Nanotube Diameter Utilizing an Artificial Cell ModelYR 2010JF Analytical ChemistrySN 1520-6882VO 82IS 3SP 1020OP 1026AB By exploiting the capabilities of steady-state electrochemical measurements, we have measured the inner diameter of a lipid nanotube using Fick’s first law of diffusion in conjunction with an imposed linear concentration gradient of electroactive molecules over the length of the nanotube. Fick’s law has been used in this way to provide a direct relationship between the nanotube diameter and the measurable experimental parameters Δi (change in current) and nanotube length. Catechol was used to determine the Δi attributed to its flux out of the nanotube. Comparing the nanotube diameter as a function of nanotube length revealed that membrane elastic energy was playing an important role in determining the size of the nanotube and was different when the tube was connected to either end of two vesicles or to a vesicle on one end and a pipet tip on the other. We assume that repulsive interaction between neck regions can be used to explain the trends observed. This theoretical approach based on elastic energy considerations provides a qualitative description consistent with experimental data.LA engDO 10.1021/ac902282dLK http://dx.doi.org/10.1021/ac902282dOL 30